Tail -f in lua, truncate aware?

["ms2008vip" <ms2008vip@...>]

Howdy:
 
          I'd like to make the output of tail -F or something similar available to me in Lua without blocking or blocking. 
      If the file gets truncated or log rotated, the program will detect it and will return to the start. This seems to be 
      a level 1 question but looks strange to me. I just can't figure it out. Does anyone could share some code? TKS
 				
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ms2008vip
2013-06-28